Range, variance and standard deviation as measures of dispersion | Khan Academy

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Пікірлер: 670

  • @zinaalabdaly6848
    @zinaalabdaly68483 жыл бұрын

    And here i am, 10 years after this was posted, learning more here in 12 min than my course in an hour Thank u from the heart of mine, khan academy !

  • @vincentdrew2194

    @vincentdrew2194

    3 жыл бұрын

    I played this at 2x speed to learn it in 6 min

  • @owenpatenaude1072

    @owenpatenaude1072

    2 жыл бұрын

    Same lo

  • @I_unar

    @I_unar

    2 жыл бұрын

    @@vincentdrew2194 That’s not smart, you might not understand everything because your brain can’t catch up. Don’t try to get everything done as quick as possible, sometimes it causes mistakes

  • @rapemap

    @rapemap

    2 жыл бұрын

    reviewing simple explanation after hours of complicated lesson often give you a new understanding and you feel enlightenment.

  • @sachimoo
    @sachimoo7 жыл бұрын

    I am taking a Statistics class online and YOU are by far the BEST thing I've come across! Your explanations are clear and thorough. You cut through all the STATISTIC jargon and allow the student to conceptualize the theory of basic statistical analyses & problems. You are truly Gifted!Thank you for sharing your knowledge and Passion.

  • @kk8490
    @kk84907 жыл бұрын

    Oh my god yes. Not all superheroes wear capes

  • @lkerzgrl24

    @lkerzgrl24

    5 жыл бұрын

    Plot twist: he was wearing a cape

  • @whitewalker608

    @whitewalker608

    5 жыл бұрын

    @@lkerzgrl24 Plot twist. OP is talking about Iron Man.

  • @kavyasoni139

    @kavyasoni139

    4 ай бұрын

    ​@@whitewalker608plot twist he is talking about Superman 😂

  • @krossthug
    @krossthug10 жыл бұрын

    i cried cos this helped me so much

  • @Zmunk19

    @Zmunk19

    9 жыл бұрын

    did it sound something like trololollololololoololollololol

  • @videogamejo

    @videogamejo

    9 жыл бұрын

    ***** Right? Isn't Khan amazing? Khan Academy makes me realize that math isn't so bad when explained properly. So many teachers and books explains things in a cryptic manner. Khan explains this stuff in layman's terms and it just clicks.

  • @madrid7790

    @madrid7790

    6 жыл бұрын

    Did you pee yourself too?

  • @ammaraa3287

    @ammaraa3287

    6 жыл бұрын

    Same!!! In class I was like what is this even and here I understood it 😂🌸🌸

  • @memoo2133

    @memoo2133

    6 жыл бұрын

    JJ not math, its statistics.

  • @coolshante7093
    @coolshante70934 жыл бұрын

    There am I scrolling down and liking every comment coz I can relate to them

  • @dotted_stains2792

    @dotted_stains2792

    Жыл бұрын

    Seeing how you have 142 likes....... I wonder

  • @harijsijabs2420
    @harijsijabs24209 жыл бұрын

    This made so much more sense than my university professor. Thanks a lot!

  • @edthoreum7625

    @edthoreum7625

    7 жыл бұрын

    great work but #are so small and the board is so dark?

  • @Anonymous-ko5ug

    @Anonymous-ko5ug

    6 жыл бұрын

    Harijs Ijabs why are you learning this in university? I'm learning this in the 6th grade

  • @FloydFilmz

    @FloydFilmz

    5 жыл бұрын

    bcuz we all have specific concepts we are learning in college such as criminal justice or law or engineering. But there are a few courses that you have to repeat that u've already learned in middle and highschool. Thats why kid.

  • @azimtwice

    @azimtwice

    5 жыл бұрын

    +FloydFilmz why'd we pay thousands to repeat what we've already learned?

  • @oliviaso9726

    @oliviaso9726

    4 жыл бұрын

    @@azimtwice idk

  • @0nly1w0rld
    @0nly1w0rld2 жыл бұрын

    This guy has done so much on Khan Academy, he should be nominated for the Nobel Prize in Education. If there isn't such a category, they should create one

  • @StopwatchRobert
    @StopwatchRobert10 жыл бұрын

    You know Mr. Khan, you and you alone are the reason this program works so well. What you teach is no different than a university professor, but the way you teach it squeezes more information into a 12 minute video than I'll get in a 50 minute lecture, and I understand it much better. I think I speak for everyone when I say I wish you were my teacher, you'd be absolutely perfect at it.

  • @murators4732
    @murators47322 жыл бұрын

    Please never delete your videos. I am also 10 years after posting learning this stuff and you are the only one who explained it the way i could understand and use it. Youe helped, help and will help millions of people. Thank you

  • @Lani2722
    @Lani27223 жыл бұрын

    Everyone is talking about their professors in university and how they're useless like 7-2 years ago I'm here in 2020 trying to figure this out in high school because I hate remote learning.

  • @Lillith9008

    @Lillith9008

    3 жыл бұрын

    that sounds very difficult dear, i can't even imagine having to do high school right now. i'm sorry you have to go through that

  • @gracemostek1976

    @gracemostek1976

    3 жыл бұрын

    same

  • @janaaa9309

    @janaaa9309

    3 жыл бұрын

    me too

  • @ikyouknoweknow

    @ikyouknoweknow

    3 жыл бұрын

    @@Lillith9008 thank u for being compassionate

  • @Supremepie
    @Supremepie Жыл бұрын

    Khan academy... helped my 14 year old self, and still helping me at 24 years old, God bless you.

  • @fabbabs
    @fabbabs9 жыл бұрын

    I have studied these concepts in at least three different classes and never understood them as well as I do now. Thank you.

  • @BrianKouhi
    @BrianKouhi8 жыл бұрын

    Amazing teaching skills, i've struggled to understand this in university for the past 2 months, with my prof being of little use. first time watching this 10min video and i completely understand it now! Thank you!

  • @122willman

    @122willman

    6 жыл бұрын

    just goes to show these universities are so overrated. they don't teach anymore. About to graduate myself and it is so funny what university teaching has become.

  • @Notabot2000
    @Notabot20005 жыл бұрын

    Learned more with this video than the first 3 weeks of college with my useless professor

  • @ZoZo-sk7mq

    @ZoZo-sk7mq

    5 жыл бұрын

    Hold on you r learning this in Uni then why am i learning this year 9 or 9th grade AUstralia IS messed up

  • @herat3158

    @herat3158

    5 жыл бұрын

    College? We're learning this in grade 9 though

  • @ZoZo-sk7mq

    @ZoZo-sk7mq

    5 жыл бұрын

    @@herat3158 thats what i said but in australia we call college uni

  • @lily-er5xt

    @lily-er5xt

    4 жыл бұрын

    I’m learning this in 7th

  • @gacharaeztrid7620

    @gacharaeztrid7620

    4 жыл бұрын

    @@lily-er5xt yeah, same.

  • @coreyw2124
    @coreyw21244 жыл бұрын

    You're so clear and cut through the jargon so well that it's actually making me mad. I spent so much time in college trying to understand this stuff and if I would have just watched these videos instead I can't even think about the amount of time and effort I would have saved. Great stuff

  • @nelsoncastillo7888
    @nelsoncastillo78888 жыл бұрын

    Your method of teaching is comprehensible, thanks

  • @HannanAli
    @HannanAli3 жыл бұрын

    If only you guys could see how the teacher teaches this subject at my university...You'd hate this subject i guarantee. She straight up reads solutions from the guide book without explaining whats happening or why we are doing anything.... Thank You So Much Khan Academy!!!

  • @jeremyrodriguez4989
    @jeremyrodriguez49893 жыл бұрын

    Currently a history major with a minor in political science. Took statistics in high school and again in college but this just made so much sense. To anyone reading the comments, watch frequency tables first and then start looking at this video. It takes15 minutes for both but you'll appreciate so much math quickly.

  • @josecuervo1646
    @josecuervo16465 жыл бұрын

    I need Sal to take my SAT for me.

  • @moizkhalid2714
    @moizkhalid27144 жыл бұрын

    Any time you feel struck in mathematics, you tune into Khan Academy where Sir Sal explaining the concept so easily.Another day is saved,thanks to Khan Academy.

  • @fangtzukang6163
    @fangtzukang61632 жыл бұрын

    The most helpful explanation about standard deviation I've ever watched. Thank you so much, Sal!!!! You're the best math teacher in the universe.

  • @HAMID___
    @HAMID___6 жыл бұрын

    Thank you u explained it so seamlessly 😭👏🏽. U save me from failing a test

  • @marysadek9683
    @marysadek96834 жыл бұрын

    This is amazing! I thought I hated stat until I watched the video. It turns out I have a bad teacher lol . The teacher who made this video made it simple and conveyed the meaning in a great way! Thank you:)

  • @saulmatakarawa9236
    @saulmatakarawa92368 жыл бұрын

    Very well explained. However, I find another explanation stating that the denominator in variance calculation should be n-1, which in this case should be 4 (5-1=4). Please clarify. Thanks

  • @manveersingh7842

    @manveersingh7842

    8 жыл бұрын

    +Saul Matakarawa I believe n-1 is to calculate the sample variance. Not 100% sure, but from what I remember.

  • @Alex-zc9ty

    @Alex-zc9ty

    5 жыл бұрын

    somebody else explained please

  • @aoa0687

    @aoa0687

    5 жыл бұрын

    vortex.ihrc.fiu.edu/MET4570/members/Lectures/Lect05/m10divideby_nminus1.pdf Check page 2

  • @pppkaew4297

    @pppkaew4297

    5 жыл бұрын

    Sample Variance’s denominator is n-1. Population variance’s is n

  • @vijayanandvadhyar7224

    @vijayanandvadhyar7224

    4 жыл бұрын

    @@pppkaew4297 thanks

  • @yrebrac
    @yrebrac4 жыл бұрын

    Khan, you legend. Needed a quick primer on this topic. You are the man.

  • @Abhishektheunofficial
    @Abhishektheunofficial7 жыл бұрын

    Thank you so much. This is so helpful. I highly appreciate the time and energy taken to prepare this to make this available for free.

  • @coronnation8854
    @coronnation8854 Жыл бұрын

    You have been helping me pass university classes for the last decade. You're a very important person in the world.

  • @user-zr4od4qg7s
    @user-zr4od4qg7s4 жыл бұрын

    I been sick for the past week and my friends told me about this because they are learning at school so I got worried since they said there's a test tomorrow but this helped a lot THANK YOU now I'm ready

  • @techvishnuyt
    @techvishnuyt Жыл бұрын

    13 years later, yup learning from here more than my professors

  • @wiifreak911
    @wiifreak91111 жыл бұрын

    This is the "Population Standard Deviation" For the "Sample Standard Deviation" we replace n with (n-1) to ensure that all desirable properties of an estimator are retained.

  • @ntbarnes656
    @ntbarnes6563 жыл бұрын

    such a great breakdown!! thank you!! you explained every step so that I understand what I am using to get each answer.

  • @mariellesiapno2494
    @mariellesiapno24945 жыл бұрын

    Thank you so much for this!!!! ♥️ You’re a blessing! ♥️🙌🏼

  • @MeganMcken
    @MeganMcken12 жыл бұрын

    I really appreciate these tutorials. I'm not a very logical/math thinker so it is nice to confirm some of my hesitancy.

  • @bsayah
    @bsayah13 жыл бұрын

    Oh my god, this never made so much sense before...thank you so much!

  • @fancydeer
    @fancydeer2 жыл бұрын

    Seriously saving me in my college class. I didn't understand any of this, it's amazing what a difference a GOOD teacher makes.

  • @gracefredericks2126
    @gracefredericks21265 жыл бұрын

    This is so helpful!! THANK YOU. You actually repeat what you're doing to help to get it in our brains and for me, it works! I didn't have to keep scrolling back. (And it also helps that you don't have a ridiculously boring monotone voice like a lot of the people who make these maths videos do)

  • @IIXIXOXIXII
    @IIXIXOXIXII11 жыл бұрын

    You spoke at a great pace and very clearly. This video was very helpful. I would like to know what the answer to evilshenanegans' question is though.. and william's question on negative numbers and range...

  • @Mahmoud-ys1kt
    @Mahmoud-ys1kt Жыл бұрын

    Simply , Its Great . Thank you

  • @williammagdales2330
    @williammagdales233011 жыл бұрын

    Dude, now im ready for my periodical test, tommorrow !! I really appreciate you pal !!!

  • @renatarech2429
    @renatarech24295 жыл бұрын

    Oh wow!! I don't normally comment of KZread videos, but you just took something that I found so confusing and complex and broke down until it was simple! Thank you ever so much

  • @timenotime
    @timenotime4 жыл бұрын

    this is SUCH a good video. i am doing a course in stats for uni and struggling so much because it's been years since i did maths (never been good at it) and i'm so happy i found this video because it's cleared up so much of what was confusing me about this whole SD vs. variance business

  • @regineyu34
    @regineyu346 жыл бұрын

    Your videos really help me get through my statistics class, thank you 💕

  • @bryanjy7923
    @bryanjy79237 жыл бұрын

    From algebra to calculus, to history, and also to statistics?! WoW! so amazed. Is Sal Khan the one that discuss in most these videos? Is he a genius? Or other way around.

  • @samizaki7165
    @samizaki71657 жыл бұрын

    The perfect way to understand the variance and the standard deviation ... Thanks KHAN Academy

  • @Naked_Snake
    @Naked_Snake12 жыл бұрын

    Haven't really used Khan Academy before, but I used this for Economics and makes perfect sense. Thank You.

  • @sameedsherazi
    @sameedsherazi3 жыл бұрын

    I don't know why but I am in love this guy's voice. And yeah the lectures being the first.

  • @xsauce3858
    @xsauce38586 жыл бұрын

    I was out of class with my friends when my lecturer was teaching this thank you so much.

  • @pieta39
    @pieta394 жыл бұрын

    I don't have enough words to thank you! You helped so many people, including me. Truly, thanks so much :)

  • @mbkfox
    @mbkfox12 жыл бұрын

    you are an amazing individual, thanks for making it simple

  • @ninagetmoney9321
    @ninagetmoney93216 жыл бұрын

    thank GOD for you!! I was stressing in class. you just made it super simple for me!

  • @Germel16
    @Germel165 жыл бұрын

    Your awesome I completely understand everything. I been having a hard time in this class but I think I understand it a little more now thankx

  • @hoomanazizi8969
    @hoomanazizi8969Ай бұрын

    I studied finance in uni and our master could not explain it as simple as this in a whole semester. thanks

  • @aishaabaniel6827
    @aishaabaniel68275 жыл бұрын

    Tanx God i found the best teacher here even you tube.nung nag aral ako walan akong naintindihan.thank you so much Sir for your help.God bless u Sir

  • @waterfairy2011
    @waterfairy20118 ай бұрын

    First time in my life I understand what is variance. Thank you so much!!!

  • @djchillsbx1
    @djchillsbx111 жыл бұрын

    yes indeed this explians it a bit better than all the other class material. Thanks!

  • @silentlessons4221
    @silentlessons4221 Жыл бұрын

    Khan academy at it again with an awesome explanation and breakdown of statistics. Thanks very much.

  • @denzilseukanundun540
    @denzilseukanundun5402 жыл бұрын

    I need this channel for Data Science! Thank you Khan Academy!

  • @kevinrandalrulach
    @kevinrandalrulach2 жыл бұрын

    I know these stuff 100%, but I need to understand these stuff with 300% confidence. Thanks for the upload.

  • @jekamiahruiz6500
    @jekamiahruiz65005 жыл бұрын

    This is cool. You have helped me a lot. Thanks to you 😊 I've also watched your videos on several topics in physics. Galing nyo po!

  • @gurpreetbhalla
    @gurpreetbhalla13 жыл бұрын

    your videos are too good and i think u are doing a great job

  • @abdulrahmankaka
    @abdulrahmankaka11 жыл бұрын

    now i get it thank you very much !

  • @eduugr
    @eduugr6 жыл бұрын

    Thank you. You are really good explaining !!

  • @minhazulislam4682
    @minhazulislam46823 жыл бұрын

    hopefully you found that useful... it was the most easiest explanation I got on the internet..My university life started a few months back (online semester ft. Corona) and I am taking a Stat course right now. My teachers explanation was really vague, it's like he(my teacher) is trying to hide something from me. but this actually cleared everything up. Thanks Salman. One day, I will be great teacher like you inshaallah.

  • @Czathero
    @Czathero11 жыл бұрын

    OMG! I love you! I finally understand this now! So happy!

  • @kimsrenglim
    @kimsrenglim6 жыл бұрын

    Vous êtes merveilleux! Merci!

  • @marj736
    @marj7367 жыл бұрын

    Khan, you are a life saver!

  • @danamclemore3805
    @danamclemore38054 жыл бұрын

    You rock - as usual. You are sooo amazing.how many people have you helped ??? You will never know

  • @philosophize24
    @philosophize246 жыл бұрын

    thank you, Khan Academy. you are saving me from failing stats.

  • @88spaces
    @88spaces4 жыл бұрын

    Your explanation is very clear and simple to understand. Thank you.

  • @adelinaa1366
    @adelinaa13668 жыл бұрын

    it really helped me! Thanks a lot!

  • @A11Omar
    @A11Omar11 жыл бұрын

    very useful. I'm taking QUAN201 and I wish I had you as my instructor 'cause mine really sucks

  • @ExploreLearnEnglishWithGeorge
    @ExploreLearnEnglishWithGeorge3 жыл бұрын

    a video explaining sample variance and population variance would be helpful.. (my synapses are shutting down)

  • @raquelporras5895
    @raquelporras58957 жыл бұрын

    Is it just me or does he sound like old Ted Mosby? Great video btw, I've been watching them before class and they are super helpful!

  • @sabrinadiego3586
    @sabrinadiego35865 жыл бұрын

    You did a great job. I followed the lecture and I could not understand. I saw your video only once and I realize that it is very easy. I think because you explain very well. thank you very much.

  • @tasbeehdeyaa
    @tasbeehdeyaa3 жыл бұрын

    Thank you so much. This.. This is exactly what I needed. It made me realize I'm not slow nor stupid it just depends on who the teacher is.

  • @saadhashmi7953
    @saadhashmi79532 жыл бұрын

    Found this vedio in my 3rd year of med school and was saved in Biostatistics. Alhamdulillah

  • @kishwarbhuiyan743
    @kishwarbhuiyan7433 жыл бұрын

    This video has helped me a lot to understand standard deviation and variance.Thanks a lot Khan Academy.

  • @hubdarali8633
    @hubdarali86333 жыл бұрын

    I have learned this topic different videos lecture but your lecture is conceptualize and clear my all confusion...thanks❤❤

  • @hugojj101
    @hugojj1016 жыл бұрын

    Ha, watched Khan academy vids when I was 10 and here I am 6 years later using them to help me with my as levels

  • @AissatouDiallo-qh7he
    @AissatouDiallo-qh7he6 жыл бұрын

    It seems very clear and helpful Thanks so much

  • @trombonetribute6433
    @trombonetribute64335 жыл бұрын

    It's summer I'm 13 and I'm learning it's my best summer yet I understood standard deviation from my math book I just didn't see that variation was standard deviation without it being square rooted it's so easy

  • @watchlearn3943
    @watchlearn39432 жыл бұрын

    Well explained. Now I was able to relate all these things. Thank you very much.

  • @parassingh6347
    @parassingh63476 жыл бұрын

    I got this blody mean deviation ....all thanxx goes to u sir ....

  • @ioannismarkoulakis4978
    @ioannismarkoulakis49786 жыл бұрын

    I normally just like the video but, this one deserves a comment. Good job, great explanation!

  • @ayobamioni5895
    @ayobamioni58955 жыл бұрын

    You're a Great Teacher! Thank you

  • @takaki_0512
    @takaki_05122 ай бұрын

    really helped! thank you

  • @waltsummerlin4848
    @waltsummerlin48485 жыл бұрын

    Thank you! It makes sense now!

  • @XinhLe
    @XinhLe7 жыл бұрын

    Thanks so much (from Southern hemisphere)!

  • @Neutrino22
    @Neutrino226 жыл бұрын

    Your every videos on mathematics is awesome. I have learned so many things. Love youuu

  • @hariiiprasath
    @hariiiprasath Жыл бұрын

    Here I am, trying to actually understand these concepts 8 years after school, and this 12 min video made me feel like my schooling had failed me.

  • @johnpastorick444
    @johnpastorick4443 жыл бұрын

    Thank you for making this more clear than the professors we pay thousands of money to

  • @kajendrarana1847
    @kajendrarana18473 жыл бұрын

    thank you for your clear explanation.

  • @bcasarez
    @bcasarez12 жыл бұрын

    The video is correct because he dealing with a population data set (also evident by the use of the sigma symbol). He explains this @ 4:45 - 5:09. You only use (n-1) when you are dealing with a sample data set (where you use "s" and not sigma).

  • @Azhucabomb
    @Azhucabomb5 жыл бұрын

    this makes so much more sense than my math class

  • @nikkishivoy9921
    @nikkishivoy99212 жыл бұрын

    The video helped me a lot in understanding Standard Deviation.

  • @LisaSmith-jo5hw
    @LisaSmith-jo5hw9 жыл бұрын

    You're a rock star! I totally get it. Thank you.

  • @mohamadosman8796

    @mohamadosman8796

    5 жыл бұрын

    how does the squire root of 400 become 2 ?

  • @Sultan-le8so
    @Sultan-le8so4 жыл бұрын

    You’re my LEGEND!!

  • @dawoodali4605
    @dawoodali46052 жыл бұрын

    Thank you soo much man!!!! Came in clutch!

  • @ahmde
    @ahmde3 жыл бұрын

    Great explanation, very intuitive.

  • @evilj3836
    @evilj38363 жыл бұрын

    That’s very helpful, Thanks.